Platen substrate sticking prevention film, substrate handling device, and substrate handling method

Abstract

To prevent a highly adhesive substrate from sticking to a platen by preventing the substrate from having a defective shape or discharging dust, reducing the burden on running costs, facilitating attachment and replacement, and effectively dealing with displacement of the substrate. SOLUTION: A resin substrate anti-stick film 1 having substrate suction holes 11 at positions corresponding to each substrate vacuum suction hole 21 on a platen 2 is placed covering a substrate placement area R of the platen 2. A sensor 3 inside the platen 2 detects misalignment of a mark 12 provided on the substrate anti-stick film 1. If the substrate anti-stick film 1 is misaligned, the operation of loading the substrate W is stopped. The substrate anti-stick film 1 is vacuum-sucked to the platen 2 through the film vacuum suction holes 25.

Description

[Technical Field]

[0001] The invention of this application relates to the handling of substrates in the manufacturing process of various products, and in particular to a technique for handling substrates placed on a platen. [Background technology]

[0002] In the manufacture of various products, we often handle base plate-like members (collectively referred to as substrates in this application). Substrates may remain in the final product, such as in printed circuit boards and liquid crystal display boards, but they may also be removed during the manufacturing process and not remain. In manufacturing processes that handle such substrates, the substrates are often placed on the surface of a member called a platen. In this application, a platen is a general term for a platform-like member on which a substrate is placed. For example, in photolithography, which creates a fine shape on a substrate, an exposure apparatus is used that irradiates a substrate with light of a predetermined pattern to expose the substrate. The exposure apparatus is equipped with a platen, and is configured to irradiate a substrate placed on the platen with light of the predetermined pattern using a mask or the like. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2001-133986 [Patent Document 2] Japanese Patent Application Laid-Open No. 2013-153146 [Patent Document 3] Japanese Patent Application Laid-Open No. 2013-146970 [Patent Document 4] Japanese Patent Application Laid-Open No. 2000-114316 [Patent Document 5] Japanese Patent Application Publication No. 10-6358 [Patent Document 6] Japanese Patent Application Laid-Open No. 2013-123849 Summary of the Invention [Problem to be solved by the invention]

[0004] In apparatuses equipped with the platen described above, there is a problem in that the substrate may stick to the platen, making it difficult to remove the substrate from the platen. For example, in printed circuit boards on which fine circuits are formed, a highly adhesive coating such as solder resist may be formed on the surface of the substrate. The coating is often also formed on the back side of the substrate that contacts the platen, and when placed on the platen, it is likely to stick due to its adhesive force. In this case, when removing the substrate from the platen after processing is completed, it may become impossible to remove, or the coating may peel off if the substrate is forcibly removed. Peeling of the coating can cause problems such as shape defects in the affected area or debris from the peeled coating becoming waste. Taking these points into consideration, devices that handle substrates with highly adhesive surfaces employ a configuration in which a metal plate with a non-stick coating, such as a fluorine-based coating, is attached to the platen and the substrate is placed on top of it.

[0005] However, metal sheets that have been treated with a non-adhesive coating have a low surface hardness, which can lead to the formation of dents or grooves in the surface due to the low hardness of the surface. If dents or grooves form in the non-adhesive surface layer of the metal sheet, they can be transferred to the substrate, damaging the product's appearance and reducing its performance. For this reason, metal sheets must be replaced after a certain period of use. However, metal sheets with this type of surface treatment are expensive, resulting in a significant burden on running costs. Furthermore, substrates often need to be placed on a highly flat surface, which requires a platen with a highly flat surface. Metal plates with non-adhesive surface treatments often have poor flatness, so they are often fixed to the highly flat surface of a platen using a method such as screwing. This makes installation and replacement time-consuming and inefficient.

[0006] Considering these problems, it has been suggested to use a resin film, such as a polyethylene terephthalate (PET) film, that has been treated to be non-sticky instead of a metal plate that has been treated to be non-sticky. However, according to the inventor's research, this type of resin film cannot be fastened with screws and must be fixed to the platen using a method such as vacuum suction. However, this fixation is sometimes insufficient, and the film is prone to slippage on the platen. If the resin film is misaligned, the substrate above it will also be misaligned, which can easily lead to defective products when performing processes that require high positional accuracy, such as exposure processes. The present invention has been made to solve the problems of the prior art as described above, and aims to prevent substrates from sticking to the platen even when handling highly adhesive substrates, thereby preventing problems such as substrate shape defects and dust emissions. Furthermore, the present invention aims to provide a device that has low running costs, is easy to install and replace, and can effectively address substrate misalignment. [Means for solving the problem]

[0007] In order to solve the above problem, the invention described in claim 1 of this application is as follows: A substrate handling method using a substrate handling device having a platen on which a substrate is placed, the method comprising: The substrate placement area of ​​the platen is covered with a platen substrate anti-sticking film, The anti-sticking film for the substrate is It has a rectangular shape overall, A number of substrate suction holes are provided in the platen to prevent the platen from being obstructed from vacuum-suctioning the substrate through the number of substrate vacuum suction holes in the platen, the numerous substrate suction holes are arranged in a line along one side of the rectangle and also in a line along another side perpendicular to the one side, the plurality of substrate suction holes are provided within a rectangular set area having sides parallel to the respective sides of the overall rectangular shape; Furthermore, a mark is provided to detect positional deviation relative to the platen, The marks are provided outside the set area and at least three of the four corners of the overall rectangular shape, the platen has a number of substrate vacuum suction holes for vacuum-sucking the substrate and film vacuum suction holes for vacuum-sucking a substrate-sticking prevention film for the platen, the substrate vacuum suction holes and the film vacuum suction holes communicating with separate exhaust passages; the plurality of substrate suction holes in the platen substrate sticking prevention film are provided at positions corresponding to the plurality of substrate vacuum suction holes in the platen, The suction through the film vacuum suction holes is a method that continues not only during handling of the substrate but also when the substrate is removed from the platen after handling is completed, The vacuum suction force of the platen substrate sticking prevention film to the platen is greater than the sticking force of the platen substrate sticking prevention film to the substrate, so that the platen substrate sticking prevention film is maintained in a state of being vacuum suctioned to the platen even when the substrate is carried out from the platen. [Effects of the Invention]

[0008] As explained below, claim 1 of this application The method for handling the substrate described According to the present invention, suction through the vacuum suction holes for the film continues not only while the substrate is being handled but also when the substrate is being transported from the platen after handling has ended, thereby reliably preventing the substrate sticking prevention film from sticking to the substrate being transported. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a perspective schematic view of a substrate sticking prevention film according to an embodiment and a platen on which the substrate sticking prevention film is used. [Figure 2] FIG. 1 is a schematic front cross-sectional view showing the substrate sticking prevention film in use. [Figure 3] 1 is a schematic front view of an exposure device as an example of using a substrate sticking prevention film and a platen according to an embodiment. [Figure 4] 10 is a flowchart showing an outline of a sequence program implemented in a controller. [Figure 5] FIG. 4 is a schematic diagram showing the operation of the exposure apparatus of FIG. [Figure 6] 10 is a schematic front cross-sectional view showing the technical significance depending on the size of the substrate suction hole. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0010] Next, a mode for carrying out the invention of this application (hereinafter referred to as an embodiment) will be described. Fig. 1 is a schematic perspective view of a substrate sticking prevention film according to an embodiment and a platen in which the substrate sticking prevention film is used, and Fig. 2 is a schematic front cross-sectional view showing the substrate sticking prevention film in use. 1 and 2 is a film that covers a substrate placement area of ​​a platen 2 on which a substrate to be processed is placed. This substrate sticking prevention film (hereinafter simply referred to as "prevention film") 1 is made of a transparent resin such as PET, and has a thickness of about 50 to 350 μm.

[0011] In this embodiment, the platen 2 is a rectangular platform on which a substrate is placed. It is assumed that the substrate to be placed is also rectangular, and therefore the substrate placement area is rectangular. The substrate placement area refers to the area on the upper surface of the platen 2 that is occupied by the placed substrate. Although substrates of different sizes and shapes may be placed on the platen, the substrate placement area is the area that is likely to be occupied by the largest substrate. In FIG. 1, the substrate placement area R is indicated by a dashed line. 1, the protection film 1 is also rectangular and is larger in size than the substrate placement area R. However, the protection film 1 is smaller in size than the upper surface of the platen 2.

[0012] The platen 2 is adapted to vacuum-suck a placed substrate and fix its position. As shown in Fig. 1, substrate vacuum suction holes 21 are formed in the substrate placement area R of the platen 2. Multiple substrate vacuum suction holes 21 are provided at equal intervals. Each substrate vacuum suction hole 21 is connected to a substrate exhaust pipe 23 through a substrate communication passage 22 provided in the platen 2. The substrate exhaust pipe 23 is connected to a vacuum pump (not shown), and a substrate open / close valve 24 is provided in the substrate exhaust pipe 23.

[0013] As shown in FIG. 1 , the protective film 1 also has a plurality of holes 11. These holes 11 are holes for vacuum-suctioning a substrate and will be referred to as substrate suction holes hereinafter. The substrate suction holes 11 are provided at positions corresponding to the substrate vacuum suction holes 21 of the platen 2 when the protective film 1 covers the substrate placement area R of the platen 2. That is, the number of substrate suction holes 11 of the protective film 1 is the same as the number of substrate vacuum suction holes 21 of the platen 2, and they are provided in the same arrangement. In this embodiment, the substrate vacuum suction holes 21 are provided in a checkerboard pattern with the same orientation as the outline of the platen 2. The substrate suction holes 11 of the protective film 1 are also in a checkerboard pattern and are provided at the same intervals and positions as the substrate vacuum suction holes 21 of the platen 2.

[0014] Such a protection film 1 is fixed in position by vacuum adsorption to the platen 2, thereby preventing the substrate from sticking. That is, the platen 2 has vacuum adsorption holes (hereinafter referred to as film vacuum adsorption holes) 25 that vacuum adsorb the protection film 1. Substrate vacuum suction holes 21 and film vacuum suction holes 25 communicate with separate exhaust pipes. A film exhaust pipe 27 is connected to platen 2 separately from substrate exhaust pipe 23. As shown in Figure 2, a film communication passage 26 is formed in platen 2 separately from substrate communication passage 22, and film communication passage 26 connects film vacuum suction holes 25 and film exhaust pipe 27. A film open / close valve 28 is provided in film exhaust pipe 27.

[0015] Such a protection film 1 is provided with a mark 12 in consideration of any misalignment that may occur on the platen 2. In this embodiment, a plurality of marks 12 are provided. Specifically, as shown in FIG. 1, the marks 12 are provided at each corner of a square. Each mark 12 is circular, and in this embodiment, serves as a reflective portion that reflects light. Each mark 12 may be a reflective portion of a color such as black or silver formed by printing or film application.

[0016] On the other hand, the platen 2 is provided with sensors 3 that detect the displacement of each mark 12 so as to determine whether or not the protection film 1 is misaligned. As shown in Fig. 2, a through-hole 29 is provided in the platen 2, and the sensors 3 are provided in the through-hole 29. In this embodiment, a fiber sensor is used as the sensor 3. The fiber sensor has a light emitting part and a light incident part at the tip of the fiber, and detects an object (here, the mark 12) by capturing reflected light of the emitted light.

[0017] The positions at which the through-hole 29 and the sensor 3 are arranged are positions that face each mark 12 when the protection film 1 is arranged in the correct position. For example, as shown in FIG. 1 , the correct position is when the center of the rectangular outline of the protection film 1 and the center of the rectangular outline of the upper surface of the platen 2 are on the same vertical line and the sides of each square are in the same direction. That is, in this embodiment, "misalignment" also includes misalignment in the rotational direction. When arranged in this position, light from the fiber sensor 3 is reflected by the marks 12 and captured, thereby detecting the marks 12. That is, the through-hole 29 and the sensor 3 are arranged at the corners of a square with the same shape and dimensions as the square formed by the four marks 12 on the protection film 1.

[0018] Next, an example of use of the protective film 1 and platen 2 of this embodiment will be described. The protective film 1 and platen 2 of the embodiment can be used in various devices that handle substrates, but in the following description, an exposure device that exposes substrates will be taken up as an example of a substrate handling device. Therefore, the following description also describes an embodiment of a substrate handling device. Fig. 3 is a schematic front view of an exposure device as an example of using the protective film 1 and platen 2 of the embodiment. The exposure device shown in Fig. 3 includes the platen 2, a light irradiation unit 4 that irradiates a substrate W placed on the platen 2 with light of a predetermined pattern to expose it, and a transport system 5 that loads the substrate W onto the platen 2 and loads the substrate W from the platen 2 after exposure.

[0019] The light irradiation unit 4 is selected and installed appropriately depending on the exposure method. The example in Figure 3 is a contact type, and the light irradiation unit 4 is configured to include a mask 41 approximately the same size as the substrate W, a platen drive mechanism 20 that brings the substrate W placed on the platen 2 into close contact with the mask 41, and an irradiation optical system 42 that irradiates a predetermined pattern of light through the mask 41. The mask 41 is held in a frame 411. In the case of a proximity type, the mask drive mechanism is configured to position the mask slightly away from the substrate W, but is otherwise basically the same as the contact type. In the case of a projection exposure type, the light irradiation unit is a projection optical system that images light transmitted through the mask onto the substrate W. Alternatively, a DI exposure method may be adopted in which a spatial light modulator such as a DMD is used to directly form an irradiation pattern without a mask.

[0020] 3, the transport system 5 is a combination of conveyors 51, 52 and transport hands 53, 54. The sets of conveyors 51, 52 and transport hands 53, 54 are provided on the loading side and unloading side, sandwiching the platen 2. Each transport hand 53, 54 has suction pads 531, 541 on the underside that hold the substrate W by vacuum suction. Each transport hand 53, 54 is provided with a hand drive mechanism 530, 540 that moves the transport hand holding the substrate W in the horizontal and vertical directions.

[0021] The exposure apparatus is equipped with an alignment means (not shown) that is arranged on the platen 2. The alignment means is composed of a camera that photographs the alignment marks of the substrate W that is arranged on the platen 2, a platen driving mechanism 20 that drives the platen 2 in accordance with the photographing results of the alignment marks to align the substrate W, and the like.

[0022] The device also includes a controller 6 that controls each part. A sequence program that operates each part in a predetermined order is installed in the controller 6. In this example, signals from each sensor 3 of the platen 2 are input to the controller 6, and these signals are provided to the sequence program as control information. More specifically, in this embodiment, each sensor 3 detects the presence or absence of reflected light. If reflected light is detected, the output of the sensor 3 is on, and if not, the output is off. Each sensor 3 sends either an on or off signal to the controller 6.

[0023] 4 is a flowchart showing an outline of the sequence program implemented in the controller 6. The sequence program is programmed to repeat the loading operation, exposure, and unloading operations for each substrate W in one lot. Before starting the loading operation, the sequence program checks the signals from each sensor 3 to determine whether any of the sensors 3 has sent an OFF signal. If an OFF signal has been sent, the sequence program is programmed to stop the loading operation. In this case, the sequence program outputs an error signal and ends.

[0024] Next, the operation of the exposure apparatus shown in Fig. 3 will be described with reference to Fig. 5, which also serves as a description of an embodiment of the invention of a substrate handling method. Fig. 5 is a schematic diagram showing the operation of the exposure apparatus of Fig. 3. The controller 6, on which the sequence program is being executed, sends a signal to the carry-in conveyor 51, which then transports the substrate W to the carry-in standby position below the carry-in transport hand (carry-in hand) 53 on the carry-in side, as shown in FIG. 5(1). At this point, the controller 6 checks the input signals from each sensor 3. If all signals are on, the controller 6 sends a signal to the hand drive mechanism 530 of the carry-in hand 53, which then transports the substrate W to the platen 2, as shown in FIG. 5(2). The substrate W is placed on the substrate placement area R of the platen 2, which is covered with the protective film 1.

[0025] Next, the controller 6 opens the substrate opening / closing valve 24. As a result, the substrate W is vacuum-adsorbed to the platen 2 by negative pressure through each substrate vacuum adsorption hole 21. Thereafter, the platen driving mechanism 20 operates, and the mask 41 is brought into close contact with the substrate W, as shown in FIG. 5(3). In this state, the controller 6 sends a signal to an alignment means (not shown) to align the substrate W. Once alignment is complete, the controller 6 sends a signal to the light irradiation unit 4 to irradiate light in a predetermined pattern. This exposes the substrate W. Once exposure for a predetermined period of time has ended, the controller 6 sends a signal to the unloading transport hand (unloading hand) 54 to unload the substrate W. The substrate W is unloaded onto the unloading conveyor 52, and is sent from the unloading conveyor 52 to the next process. Then, when the next substrate W is positioned at the loading standby position, the same operation is repeated.

[0026] In the above operation, if the signal from any of the sensors 3 is off when the substrate W is positioned at the carry-in standby position, an error signal is output as described above, and the carry-in operation of the substrate W is not performed. In this case, the apparatus is in a stopped state. In this case, the substrate W preceding the substrate W in question may already have been carried out from the platen 2 and may be positioned on the unloading conveyor 53. In this case, the unloading operation of the unloading conveyor 53 may continue even after the apparatus has stopped. In the above exposure device, the controller 6 always sends an open signal to the film on-off valve 28 while the device is in operation. Therefore, the protection film 1 is always vacuum-adsorbed to the platen 2 while the device is in operation.

[0027] According to the protective film 1 of the above-described embodiment, the protective film 1 has substrate suction holes 11 for vacuum-suctioning the substrate W at positions corresponding to the substrate vacuum suction holes 21 of the platen 2, so that the vacuum suction of the substrate W is not hindered even when the substrate placement area R of the platen 2 is covered to prevent the substrate W from sticking. Furthermore, the protective film 1 of the embodiment has marks 12 for detecting positional deviation with respect to the platen 2 at positions away from the substrate suction holes 11, so that positional deviation of the protective film 1 can be detected by detecting the deviation of the marks 12.

[0028] If the mark 12 is not provided and misalignment of the protection film 1 cannot be detected, the protection film 1 may be misaligned and the substrate W may be placed in a state where it blocks the substrate vacuum suction holes 21 of the platen 2. In this case, the vacuum suction force will not be applied to the placed substrate W, or the vacuum suction force will be insufficient. This will result in serious problems such as the inability to align the substrate W. On the other hand, since the protective film 1 of the embodiment is provided with the mark 12 as described above, by providing some means for detecting the misalignment of the mark 12, it is possible to easily detect the misalignment of the protective film 1, and to prevent errors such as placing the substrate W on the platen 2 when vacuum suction is not possible.

[0029] Furthermore, the platen 2 of this embodiment is equipped with vacuum suction holes 25 for the film, which vacuum-sucks the protective film 1, eliminating the need to fasten the protective film 1 with screws. This allows the use of inexpensive resin films such as PET, significantly reducing the burden on running costs. Furthermore, the platen can be removed simply by turning off the vacuum suction, and can be attached by simply setting it in the designated position and turning on the vacuum suction, making it extremely easy to do.

[0030] Furthermore, in the platen 2, the substrate vacuum suction holes 21 and the film vacuum suction holes 25 are connected to separate exhaust pipes 23 and 27, respectively, so the protective film 1 can be vacuum-sucked at all times, independent of the suction and holding operation of the substrate W. If the substrate vacuum suction holes 21 and the film vacuum suction holes 25 were not connected to separate exhaust pipes, the vacuum suction of the protective film 1 would also be turned on when the substrate W was vacuum-sucked. Therefore, the protective film 1 would not be vacuum-sucked until then, making it prone to misalignment. While it would be possible to keep both vacuum suctions operating at all times, this would result in the substrate W being placed on a vacuum-sucked suction hole, which would cause the placement operation to become unstable. The platen 2 of the embodiment does not have this problem, which is why the substrate handling device of the embodiment equipped with the platen 2 has an advantage.

[0031] Furthermore, the fact that the sensor 3 for detecting the mark 12 on the protection film 1 is provided on the platen 2 is significant in simplifying the structure of the device equipped with the platen 2. As a means for detecting the mark 12 on the protection film 1, a configuration in which the sensor 3 is provided at a location other than the platen 2 is also conceivable. For example, a configuration in which a sensor (for example, an image sensor such as a camera) is placed above the platen 2 and the deviation of the mark 12 is monitored from above is also conceivable.

[0032] However, structures for handling or processing the substrate W placed on the platen 2 are often disposed above the platen 2. The light irradiation unit 4 in the exposure apparatus described above is one example. Due to such structures, it is often difficult or impossible to dispose a positional deviation detection means such as the sensor 3 above the platen 2. For example, in the exposure apparatus described above, a configuration in which a camera is disposed above the platen 2 and an advance / retract mechanism for retracting the camera during operation of the light irradiation unit 4 is considered, but this would be structurally large and would require complex and time-consuming operation. In comparison, a platen 2 equipped with a sensor 3 can simplify the structure and operation of the entire apparatus, and in this respect is advantageous.

[0033] Furthermore, the protective film 1 of the embodiment has a mark 12 outside the area where the substrate suction holes 11 are provided. The "area where the substrate suction holes are provided" corresponds to the area of ​​the protective film 1 that is covered by the substrate W when the substrate W is placed on it. The fact that the mark 12 is provided outside this area means that the mark 12 is not covered by the substrate W even when the substrate W is placed on it. This structure is significant in that the mark 12 can be easily detected at all times.

[0034] If the mark 12 is located in a position that is covered by the substrate W, the sensor 3 on the platen 2 of the embodiment captures reflected light, and therefore will output an ON signal by capturing reflected light from the substrate W even if the mark 12 is misaligned. In other words, even if the protective film 1 is misaligned, it will be determined that it is not misaligned. While it is possible to use a high-performance sensor 3 such as a color image sensor so that the mark 12 can be detected even when it is overlapped with the substrate W, this would result in problems such as high costs, complicated image data processing, and time consumption. Therefore, the protective film 1 of the embodiment, in which the mark 12 is formed in a position that is not covered by the substrate W, is significant in that it allows for easy detection of misalignment with a simple configuration.

[0035] 3, the frame 411 of the mask 41 is located above the platen 2. During exposure of the substrate W, the mask is in contact with the substrate W, and the frame 411 is located immediately above the platen 2. During exposure, if the frame is located behind the mark 12 on the protection film 1, the sensor 3 may capture the light reflected by the frame 411 even if the mark 12 is misaligned. Therefore, in the exposure apparatus shown in FIG. 3, it is desirable to check the signal from the sensor 3 when the frame 411 is separated from the platen 2. However, if the frame 411 is positioned away from the sensor 3 and the through-hole 29, or if there is no frame (for example, in the case of a projection exposure method), such consideration is not necessary, and the positional deviation of the protection film 1 can be monitored at all times.

[0036] Furthermore, in this embodiment, the protection film 1 is provided with multiple marks 12. This allows for reliable detection of misalignment. While it is possible to detect misalignment with only one mark 12, it is not possible to detect misalignment in the rotational direction around that mark 12. This type of misalignment can also block the substrate vacuum suction holes 21 of the platen 2, so it is preferable to make it detectable. This can be easily achieved by providing multiple marks 12 for detection. In the above example, there were four marks 12, but two or three marks would also be acceptable.

[0037] In the embodiment of the substrate handling method described above, it is more preferable to transport the substrate W after confirming that the film vacuum suction holes 25 are closed. Specifically, a pressure sensor is provided on the film exhaust pipe 27, and the output of the pressure sensor is input to the controller 6. The sequence program on the controller 6 is programmed to check the closure of the film vacuum suction holes 25 from the output of the pressure sensor, and to transport the substrate W after confirming that they are closed (i.e., that the protection film 1 is vacuum-sucked).

[0038] Although the mark 12 is detected correctly and there is no misalignment of the protection film 1, it is possible that the vacuum suction of the protection film 1 is not working due to some error. If the substrate W is transported and placed on the platen 1 in this state, the protective film 1 may be misaligned due to the momentum of being placed on the platen. If this occurs, the protection film 1 may block the vacuum suction holes 21 for the substrate, preventing vacuum suction of the substrate W, or causing the substrate W to be misaligned. As described above, if the vacuum suction of the protection film 1 is confirmed to be on in advance, such a problem will not occur.

[0039] In the protective film 1 of the above-described embodiment, the substrate suction holes 11 are smaller than the substrate vacuum suction holes 21 of the platen 2. This is particularly significant for substrates with soft surfaces, such as those with solder resist. Conversely, if the substrate suction holes 11 are larger than the substrate vacuum suction holes 21 of the platen 2, it is significant to increase the tolerance for misalignment of the protective film 1. These points will be explained using FIG. 6, which is a front cross-sectional schematic diagram showing the technical significance of different sizes of substrate suction holes.

[0040] The substrate W may have a soft surface. A typical example is a substrate with solder resist, which is often also coated on the back side. On the other hand, when the substrate suction holes 11 are formed by drilling holes in a resin sheet, the edges tend to become sharp like burrs. For this reason, when a substrate W with a soft surface such as a substrate with solder resist is pressed with a certain amount of force, marks from the edges of the substrate suction holes 11 tend to remain on the surface of the substrate W. If marks remain, the product not only looks bad, but may also cause performance problems.

[0041] As described above, the protection film 1 of this embodiment is a flexible resin film with a thickness of approximately 50 to 350 μm. Therefore, when the substrate W is placed on it and vacuum-sucked, the vacuum suction force causes the edges of the substrate suction holes 11 to bend toward the back of the substrate vacuum suction holes 21, as shown in FIG. 6(A). This makes it difficult for the edges of the vacuum suction holes 11 to leave marks on the back surface of the substrate W. The smaller the substrate suction holes 11, the greater the amount of bending, making this effect more reliable. However, if they are too small, care must be taken because the conductance during vacuum suction decreases. If the substrate suction holes 11 are circular, it is practically preferable to make the diameter no smaller than 2 mm.

[0042] Conversely, if the substrate suction holes 11 are larger than the substrate vacuum suction holes 21 of the platen 2, as shown in FIG. 6(B), even if the protection film 1 is slightly misaligned, the substrate vacuum suction holes 21 will not be blocked. In other words, the tolerance for misalignment is higher. In this case, the larger the substrate suction holes 11, the greater the tolerance for misalignment. However, as the substrate suction holes 11 become larger, the area of ​​the platen 2 that is not covered increases accordingly, and this results in a significant local decrease in the effectiveness of preventing the substrate W from sticking. Therefore, when the substrate suction holes 11 and the substrate vacuum suction holes 21 are circular, it is practically preferable that the diameter of the substrate suction holes 11 be approximately 2 mm larger than the diameter of the substrate vacuum suction holes 21. Furthermore, if the substrate suction hole 11 is larger than the substrate vacuum suction hole 21, the above problem may occur in the case of a substrate with solder resist, but this problem can be prevented by increasing the hardness of the solder resist by sintering the solder resist, etc.

[0043] In the above embodiment, the protection film 1 is entirely transparent and the mark 12 is a reflective portion, but the reverse is also possible. For example, the protection film 1 may be made entirely opaque by a method such as coating, with some transparent portions remaining as marks 12. Alternatively, the marks 12 may be cut out in parts. In this case, it is normal for the sensor 3 not to capture reflected light, and if it does capture reflected light, it will be determined that a positional deviation has occurred.

[0044] As the sensor 3, in addition to the above-mentioned fiber-type photoelectric sensor, it is also possible to use other types of sensors such as a magnetic sensor or a proximity sensor. Furthermore, the protective film 1 of the present invention can be used in various devices for processing substrates, in addition to the exposure device described above. The protective film 1 of the present invention can be used on the platen 2 not only in processing devices but also when handling substrates for various inspections, tests, etc. This also applies to the invention of the substrate handling method. [Explanation of symbols]

[0045] 1. Anti-stick film for circuit boards 11 Board suction hole 12 marks 2 Platens 21 Vacuum suction hole for substrate 22 Communication path for board 23 Exhaust pipe for circuit board 24 Substrate on-off valve 25 Vacuum suction holes for film 26 Film connection passage 27 Film exhaust pipe 28 Film on-off valve 29 Through holes 3 sensors 4 Light irradiation unit 5. Transport system 6 Controller W substrate R Substrate placement area

Claims

[Claim 1] A substrate handling method using a substrate handling device having a platen on which a substrate is placed, the method comprising: The substrate placement area of ​​the platen is covered with a platen substrate anti-sticking film, The anti-sticking film for the substrate is It has a rectangular shape overall, A number of substrate suction holes are provided in the platen to prevent the platen from being obstructed from vacuum-suctioning the substrate through the number of substrate vacuum suction holes in the platen, the numerous substrate suction holes are arranged in a line along one side of the rectangle and also in a line along another side perpendicular to the one side, the plurality of substrate suction holes are provided within a rectangular set area having sides parallel to the respective sides of the overall rectangular shape; Furthermore, a mark is provided to detect positional deviation relative to the platen, The marks are provided outside the set area and at least three of the four corners of the overall rectangular shape, the platen has a number of substrate vacuum suction holes for vacuum-sucking the substrate and film vacuum suction holes for vacuum-sucking a substrate-sticking prevention film for the platen, the substrate vacuum suction holes and the film vacuum suction holes communicating with separate exhaust passages; the plurality of substrate suction holes in the platen substrate sticking prevention film are provided at positions corresponding to the plurality of substrate vacuum suction holes in the platen, The suction through the film vacuum suction holes is a method that continues not only during handling of the substrate but also when the substrate is removed from the platen after handling is completed, This substrate handling method is characterized in that the vacuum suction force of the platen substrate anti-sticking film to the platen is greater than the adhesion force of the platen substrate anti-sticking film to the substrate, so that the platen substrate anti-sticking film is maintained in a vacuum suctioned state to the platen even when the substrate is carried out from the platen.

Images